摘要
利用端氨基偶联剂KH-550对纳米SiO2进行表面改性,在超声场作用下制备疏水性纳米SiO2粒子,并将其均匀分散到蓖麻油(CO)-聚氨酯溶液,通过红外光谱(IR)、热重分析(TGA)和扫描电镜(SEM)等测试方法,探讨醇溶性聚氨酯的热稳定性、铅笔硬度和胶膜力学性能等。红外分析表明,PU大分子和纳米SiO2之间形成化学键,形成了Si—O—Si结构。当蓖麻油添加量为多元醇总质量的10%时,拉伸强度由原来的6.8 MPa增加到16.2 MPa,吸水率降低至原来的1/2。纳米SiO2颗粒掺杂量由0%增加到2%时,PU涂膜的失重速率最高点温度由原来的345℃提高至369℃,热分解温度也有所提高。涂膜热重曲线出现右移。
Hydrophobic nano-SiO2 particles were prepared through the reaction of coupling agent KH-550 with nano SiO2 particles under the action of ultrasound,and subsequently dispersed in polyurethane solution modified by castor oil（CO）.The performance of polyurethane was characterized by means of fourier transform infrared（FTIR） spectroscopy,thermal gravimetric analysis（TGA） and scanning electron microscopy（SEM）.The FTIR analysis indicates the formation of chemical bond between PU and nano-SiO2,thus forming the Si—O—Si particle structure.When castor oil dosage was 10% of the total amount of polyol,the tensile strength of the film increased from 6.8 MPa to 16.2 MPa,and the water absorption also decreased by more than two times.When the mass fraction of nano-SiO2 increased from 0% to 2%,the highest point temperature of mass loss rate of PU film increased from 345 ℃ to 369 ℃,with an incidental increase of thermal decomposition temperature.TGA curves of the coating manifested a shift to the right.
出处
《精细化工》
EI
CAS
CSCD
北大核心
2012年第10期1021-1025,共5页
Fine Chemicals
